High severity · published Jun 8, 2026
CVE-2026-42536
Apache HTTP Server: mod_xml2enc heap overflow
7.5
CVSS
1%
EPSS
No
On KEV
Description
Heap-based Buffer Overflow vulnerability in Apache HTTP Server with mod_xml2enc, xml2StartParse, and untrusted content
This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67.
Users are recommended to upgrade to version 2.4.68, which fixes the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 63% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HS
HTTP Server · Apache
2.4.0 through 2.4.67 · source: vendor, NVD
JC
JBoss Core Services for RHEL 8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 10.0 Extended Update Support · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 6 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 7 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 9.6 Extended Update Support · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Hardened Images · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Insights proxy 1.5 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-42536
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-42536
Vendor Advisory
https://httpd.apache.org/security/vulnerabilities_24.html
Mailing List
http://www.openwall.com/lists/oss-security/2026/06/08/9
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:25042
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:34109
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:41906
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:42828
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